Chipai unveiled Google Duplex to an eager crowd roaring with applause, and demonstrated the new tool making a real call to a hair salon. It is nearly impossible to discern which voice belongs to the human, and which belongs to the bot making the call, complete with natural pauses, inflection and crutches like “uh” and “um.”

The development is yet another step into a surreal new world, one reminiscent of HBO’s “West World,” where a character who is asked if she is real, responds, “Well, if you can’t tell, it doesn’t matter.”

“The amazing thing is that the assistant can actually understand the nuances of conversation,” said Chipai. “We’ve been working on this technology for many years.”

This summer, Google will start testing the Duplex technology within Google Assistant, to help users make restaurant reservations, schedule salon appointments and get holiday hours over the phone.

“By the way, when you are done, the assistant can give you confirmation notification, saying your appointment has been taken care of,” said Chipai.